1. Field of the Invention
The invention generally relates to an available-to-promise method executed and/or executable on a computer, the method being suitable for determining the earliest delivery date for a demand on the basis of a fact table, the demand specifying a desired date and a desired quantity for items from a stock, the fact table being stored in a database connected to the database management system. The invention further relates to a computer comprising means for performing such a method and to a computer program that, when run on a computer, carries out such a method.
2. Description of the Related Art
Unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
There is an ongoing discussion in the database community to what extent applications may benefit from a database management system (DBMS) that exactly suits their needs. One central paper in this discussion is written by Stonebraker and çetintemel [Michael Stonebraker and Ugur çetintemel. “One Size Fits All”: An Idea Whose Time Has Come and Gone (Abstract). In ICDE, pages 2-11. IEEE Computer Society, 2005] who argue that applications, such as text search, scientific applications, data warehousing, and stream processing, can benefit in view of performance, maintenance, and functionality by using application specific database engines. According to Krueger et al. [Jens Krüger, Christian Tinnefeld, Martin Grund, Alexander Zeier, and Hasso Plattner. A case for online mixed workload processing. In Shivnath Babu and G. N. Paulley, editors, DBTest. ACM, 2010], this statement holds true for the domain of traditional enterprise applications and—as exemplified in this patent application—particularly for an available-to-promise (ATP) application.
ATP applications typically relate to supply chain management (SCM) systems and provide a checking method that determines whether items of desired products of a customer order can be delivered on a requested date. This functionality is achieved by comparing the quantities of items of a desired product that are in stock or scheduled for production with the quantities that are assigned to already promised orders [Jörg Thomas Dickersbach. Supply Chain Management with APO. Springer, Berlin, Heidelberg, 2005, Rainer Scheckenbach and Alexander Zeier. Collaborative SCM in Branchen. Galileo Press GmbH, Bonn, 2003]. Product in the sense of this patent application is a category of items, the items of this category exhibiting specific characteristics. To this regard, an item may be any commodity, such as a tangible good, physical object, or an intangible service, in so far as the commodity may be booked or reserved for discrete time intervals.
A common technique in current SCM systems with ATP functionality is using materialized aggregates for keeping track of the different stock item quantities, materialized aggregates being database objects containing copies of query results (e.g., results of an ATP check). In particular, an individual materialized aggregate is provided not only for each different product but also for each time interval of interest. These materialized aggregates are continuously updated so that a new item of a product in stock increases the value of the corresponding materialized aggregate while the assignment of items of a product to a confirmed customer order decreases the latter.